2001 F-350, 7.3L,
Has done this off & on for a few years and am tired of it! Noise is kind of a buzzing that seems to come from the flasher/turn signal relay. It stops buzzing when you turn on a turn signal, activate the flashers, or lift up on the shifter arm(?). Had to drive home yesterday with the flashers on! So I see from researching that it may actually be the multi-funtion switch on the steering column. So I removed that, cleaned up all the contacts, and put it back on and the buzzing did not go away.

So . . . . ??? whadaya suppose it is? Which part do I replace?

 

Might try a new flasher relay- Probably easiest thing to try

 

But I've read several posts throughout forums that it's the multi-function switch that is the culprit. "Buzzing never went away after replacing relay" . . .

 

Tried a new multi-switch . . . didn't fix it. WTF??!!

 

Q: When it's "Buzzing" do any of the lights come on - may be very dim, you'll have to look closely. Remove the socket to make it easier.

There are only two possibilities. One being the Coil Side of the Relay is weak. And, Two, there is a short in the field circuit which back-feeds the relay.

The latter is the most difficult to find. But, you can disconnect the entire rear of the vehicle at a harness connector where the Cab meets the Bed. That will eliminate 50% of the lighting but only about 25% of the wiring.

The remainder needs to done using a wiring diagram going splice to splice and connection to connection and anything in-between.

 

No, no lights come on. Buzzing is intermittant, and can be made to quit when any of the turn signal lights are on. L, R, or emergency flahsers. Also, when touching the brake pedal. This has been an on again, off again issue for a few years. I removed the knee panel to access stuff and can wiggle a connector under there and make it stop also.
Related side note: this truck has gone through several alternators over the 10 years I've owned it (thank God for lifetime warranty's) and I would almost remember this buzzing occuring around the same time the alternator goes out. I'm going to get it checked today.

 

Check for a shorted or loose connection in that molex

 

O.K. . . . . what's a molex?

 

A molex plug is a plastic connector. Has male stabs on one side & female on the other. When u said in the post # 6 that you wiggled a connector I just thought it to be a molex connector. Maybe not. Either way it sounds like u may have located the problem. Just have to find which wire or connection is loose.

 

Will do.. I will also spray them with some contact cleaner to get rid of any corrotion/dust/etc.

 

There u go - Let us know back if & what u find.

 

Just for grins, set your meter to AC volts and see what you have coming out of the alternator....

 

I was going to . . . then went to parts store and had them hook up their analyzer. Batteries, Starter, and alternator are all showing good.

 

I wouldn't count on that being entirely accurate if they tested everything installed on the truck itself.

-Batteries should be tested after a cold soak overnight. This is a better way to test if they batteries are actually good.

 

Mine has been doing the exact same thing for several years now, on and off. Springer Pop even offered to take the whole dash off is necessary to find the buzzing, but when I got there, it had quit. Very frustrating.